CN102829918A

CN102829918A - Loading method of differential vertical micro force loading device

Info

Publication number: CN102829918A
Application number: CN2012103194404A
Authority: CN
Inventors: 王勇; 刘晓峰; 王秋杰; 刘焕进; 刘正士
Original assignee: Hefei University of Technology
Current assignee: Hefei University of Technology
Priority date: 2011-07-27
Filing date: 2011-07-27
Publication date: 2012-12-19
Anticipated expiration: 2031-07-27
Also published as: CN102829918B

Abstract

The invention discloses a loading method of a differential vertical micro force loading device. The loading method is characterized in that the middle part of a horizontally placed secondary lever is provided with a secondary supporting point, wherein a pair of primary levers is separately and symmetrically arranged on two sides of the secondary supporting point in the same vertical plane by taking the secondary supporting point as a center, and is connected with the secondary lever through transition rods on respective sides respectively. The loading method can be used for calibrating a micro force sensor, a micromechanical system and various micro force detectors and provides support for a force measuring system of a micro force value.

Description

The loading method of differential type vertical micro force loading device

The application is: 20110727, application number is: 2011102124289, denomination of invention is: the dividing an application of the application for a patent for invention of differential type vertical micro force loading device and loading method.

Technical field

The present invention relates to be applied in the loading method of the micro-force loading device in the field of measuring technique.

Background technology

Flourish along with modern science and technology; Need the occasion of little small value force more and more; For example the Research on Mechanical Properties of microscale lower member in the MEMS, Micro Lub phenomenon are measured, little power detection etc. in the assembling of micro sensing Micro-Robot; Therefore, the research of Micro-force sensor, making, production are also with regard to thereupon carrying out.But its research is made relatively, and the performance measurement development of Micro-force sensor itself seems and relatively lags behind.The conventional at present pulley counterweight method of using can't be carried out little power loading force; Existing Lorentz force and electrostatic force scaling method are because of the more instability of bringing of affected factor; Utilize piezoelectric element to produce the applied more and more of little power in recent years, but this method cost is high, complicated operation, and the power scope that produces is less.

Flexure hinge mechanism is used widely in fields such as precision measurement, demarcation; But about flexible hinge distortion, lever centre of gravity place and variation of temperature to measuring and the influence of stated accuracy still lacks comprehensive consideration and research; Do not see so far about dependency structure design for elimination gravity and temperature two aspect factor affecting, and when little power is demarcated or measured, in order to obtain higher precision; Must solve of the influence that demarcation or measurement caused of above several respects to little power; Because the influence that gravity and temperature produce possibly be far longer than the maximum range that little power loads, little power is loaded the fatal influence of generation.

Summary of the invention

The present invention is for avoiding the existing weak point of above-mentioned prior art; A kind of the satisfy requirement of certain precision power value and the loading method of differential type vertical micro force loading device cheaply are provided; Be used for Micro-force sensor, MEMS and various little force detector are demarcated, and provide support for the dynamometric system of little small value force.

Technical solution problem of the present invention adopts following technical scheme:

The loading method of differential type vertical micro force loading device of the present invention is characterized in:

Said differential type vertical micro force loading device is set is: the middle part at the second lever of horizontal positioned is provided with the secondary fulcrum; With said secondary fulcrum is the center; In same perpendicular; A pair of one-level lever symmetry is divided the both sides that are in the secondary fulcrum, and connects mutually with second lever through the transiting rod of a side separately respectively.

Said one-level lever is horizontal positioned; Load counterweight and be arranged on bar outer end as the one-level lever of input end; The one-level fulcrum is positioned at the middle part of one-level lever; Bar the inner of one-level lever is connected the top of transiting rod at the bar sidepiece through the one-level flexible hinge, and the bottom of said transiting rod is connected with the rod end sidepiece of second lever through the secondary flexible hinge; One end along continuous straight runs of said second lever extends, and forms free end through the extension, at the free end of said second lever probe is set, and contacts with force transducer on being arranged on micromotion platform with said probe.

Middle part at said transiting rod is provided with the transiting rod balancing weight through the cantilever that connects firmly, and makes the center of gravity of transiting rod adjust to place, secondary flexible hinge position; Bar outer end at said one-level lever is provided with one-level lever balancing weight, makes the center of gravity of said one-level lever adjust to the position of one-level fulcrum; Restrain end at said second lever is provided with the second lever balancing weight, makes second lever and extension thereof, transiting rod, cantilever and the common center of gravity of transiting rod balancing weight adjust to the position of secondary fulcrum.

The loading method of differential type vertical micro force loading device of the present invention is to realize differential loading by one of following mode:

Mode one, load the loading counterweight of equal in quality at two input ends, this moment, probe was on the initial position; Force transducer is set keeps motionless, change the quality difference that two input ends load counterweight, on said force transducer, obtain the loading force of different sizes at initial position;

Mode two, load the loading counterweight of equal in quality at two input ends; This moment, probe was on the initial position, changed the quality difference that two input ends load counterweight then, made probe skew occur; By force transducer probe is progressively passed initial position from the position of skew; Force transducer is near more apart from initial position, and probe is big more to the acting force of force transducer, and the displacement that finally loads quality difference and the force transducer of counterweight by two input ends determines the size of loading force.

The design feature of the vertical micro of differential type described in the present invention force loading device also is at said one-level fulcrum and secondary position of the fulcrum place; One-level lever and second lever are suspended on the pedestal through each supports flexible hinge respectively, and said each supports flexible hinge becomes consistent with gravity direction.

Compared with present technology, beneficial effect of the present invention is embodied in:

1, the present invention is based on flexible hinge and lever principle has set up a kind of second lever power and has dwindled mechanism; Be used to produce micro force, utilize the counterweight loading force, simple and reliable, easy to operate; Can carry out dynamic load within the specific limits, can be widely used in multiple occasion;

2, Applications of Flexure Hinge of the present invention has reduced the friction link in the calibration system, has improved stated accuracy.

3, the present invention at first makes the center of gravity of transiting rod adjust to secondary flexible hinge position through each balancing weight is set, and the common center of gravity of transiting rod that makes second lever then and have a counter weight construction is adjusted at secondary position of the fulcrum place; The center of gravity of one-level lever is adjusted on the one-level position of the fulcrum, has eliminated center of gravity and changed the influence that each rod member is caused, make little power of generation more stable, anti-interference factor is strong;

4, the present invention adopts symmetrical mechanism, has eliminated Influence of Temperature, has improved the power loading accuracy.

5, the flexible hinge at one-level fulcrum of the present invention and secondary fulcrum place all adopts with gravity direction and becomes consistent setting, has eliminated flexural deformation and bending stress that gravity causes flexible hinge, otherwise, the destruction that the moment of flexure that gravity produces can cause flexible hinge.

Description of drawings

Fig. 1 is vertical micro force loading device schematic diagram among the present invention;

Label among the figure: 1 second lever; 2 secondary fulcrums; 3 one-level levers; 4 load counterweight; 5 one-level fulcrums; 6 one-level flexible hinges; 7 transiting rods; 8 secondary flexible hinges; 9 probes; 10 micromotion platforms; 11 force transducers; 12 one-level lever balancing weights; 13 second lever balancing weights; 14 second lever extensions; The 7a cantilever; 7b transition lever balancing weight.

Embodiment

Referring to Fig. 1, present embodiment differential type vertical micro force loading device includes: a pair of one-level lever 3, second lever 1, a pair of transiting rod 7 and a pair of one-level lever balancing weight 12, a pair of cantilever 7a, a pair of transiting rod balancing weight 7b and a second lever balancing weight 13; In the present embodiment; At the middle part of the second lever that is horizontal positioned 1 secondary fulcrum 2 being set, is the center with secondary fulcrum 2, in same perpendicular; A pair of one-level lever 3 symmetries are divided the both sides that are in secondary fulcrum 2, and connect mutually with second lever 1 through the transiting rod 7 of a side separately respectively;

One-level lever 3 is horizontal positioned; Load counterweight 4 and be arranged on bar outer end as the one-level lever of input end; One-level fulcrum 5 is positioned at the middle part of one-level lever 3; Bar the inner of one-level lever 3 is connected the top of transiting rod 7 at the bar sidepiece through one-level flexible hinge 6, and the bottom of transiting rod 7 is connected with the rod end sidepiece of second lever 1 through secondary flexible hinge 8; One end along continuous straight runs of second lever 1 extends; And 14 form free ends through the extension; Free end at second lever 1 is provided with probe 9, contacts with force transducer 11 on being arranged on micromotion platform 10 with probe 9, is moved at vertical direction by micromotion platform 10 drive sensors 11.

Change the influence that each rod member is caused in order to reduce or to eliminate center of gravity; Balancing weight is set: at first through the cantilever 7a that connects firmly transiting rod balancing weight 7b is set, makes the center of gravity of transiting rod 7 adjust to place, secondary flexible hinge 8 positions respectively at the middle part of transiting rod 7 on the relevant position of each rod member; At the restrain end place of second lever 1 second lever balancing weight 13 is set then, make second lever 1 and extension 17 thereof, transiting rod 7, cantilever 7a and transiting rod balancing weight 7b common center of gravity adjust on the position of secondary fulcrum 2; Bar outer end at one-level lever 3 is provided with one-level lever balancing weight 12, makes the center of gravity of one-level lever 3 adjust to place, one-level fulcrum 5 positions;

Change the influence that each rod member is caused in order to reduce or to eliminate center of gravity, the setting of balancing weight also can be:

At first through the cantilever 7a that connects firmly transiting rod balancing weight 7b is set, makes the center of gravity of transiting rod 7 adjust to place, one-level flexible hinge 6 positions at the middle part of transiting rod 7; Bar outer end at one-level lever 3 is provided with one-level lever balancing weight 12 then, makes one-level lever 3, transiting rod 7, cantilever 7a and the common center of gravity of transiting rod balancing weight 7b adjust to the position of one-level fulcrum 5; At last second lever balancing weight 13 is set, the center of gravity of second lever 1 and extension 14 thereof is adjusted on the position of secondary fulcrum 2 at the restrain end place of second lever 1.

In the practical implementation, can remove transiting rod balancing weight 7b, but can reduce measuring accuracy and reduce the force measurement scope.

In one-level fulcrum 5 and secondary fulcrum 2 positions; One-level lever 3 is respectively to be suspended on the pedestal through each supports flexible hinge with second lever 1; In order to eliminate flexural deformation and the bending stress that gravity causes each supports flexible hinge; The destruction that the moment of flexure of avoiding gravity to produce causes the supports flexible hinge, the supports flexible hinge at one-level fulcrum and secondary points place are all adopted and are become consistent setting with gravity direction.

Whole device produces little power by counterweight; Little power is much smaller than the quality of counterweight; And one-level flexible hinge 6 is big more to the ratio of the distance of one-level fulcrum 5 with the input end of one-level lever 3 to the distance of one-level fulcrum 5; Probe 9 is big more to the ratio of the distance of secondary fulcrum 2 with secondary flexible hinge 8 to the distance of secondary fulcrum 2, then just can produce more little little power.

Differential type vertical micro force loading device is realized differential loading by one of following mode in the present embodiment:

Mode one, load the loading counterweight of equal in quality at two input ends, this moment, probe was on the initial position; Force transducer is set keeps motionless at initial position; Change the quality difference that two input ends load counterweight, the loading force that makes one of them input end is F1a, and the loading force of another input end is F1b; The power difference F1=F1a-F1b that is then loaded; This power difference is loaded on the force transducer 11 through probe after dwindling through flexure hinge mechanism, thereby obtains little power of different sizes;

Mode two, load the loading counterweight of equal in quality at two input ends; This moment, probe was on the initial position; Change the quality difference that two input ends load counterweight then, make probe skew occur, probe is progressively passed initial position from the position of skew by force transducer; Force transducer is near more apart from initial position; Probe is big more to the acting force of force transducer, and the displacement that finally loads quality difference and the force transducer of counterweight by two input ends determines the size of loading force, and a non-contact displacement transducer can be set at the probe place; Through theoretical analysis, numerical evaluation and experimental calibration, be based upon different two input ends and load the quality difference test pin biasing displacement of counterweight and the relation between loading force.

Measurement mechanism of the present invention can realize 10 ^-2Following little power loads.

Claims

1. A loading method of a differential vertical micro-force loading device, characterized in that:

Setting the differential vertical micro-force loading device is: setting a secondary fulcrum (2) in the middle of the horizontally placed secondary lever (1), with the secondary fulcrum (2) as the center, in the same vertical plane, a The first-level lever (3) is symmetrically located on both sides of the second-level fulcrum (2), and is connected with the second-level lever (1) through the transition rod (7) on each side;

The first-level lever (3) is placed horizontally, the loading weight (4) is arranged on the outer end of the first-level lever as the input end, the first-level fulcrum (5) is located in the middle of the first-level lever (3), and the first-level lever The inner end of the rod (3) is connected to the top of the transition rod (7) at the side of the rod through a primary flexible hinge (6), and the bottom end of the transition rod (7) is connected to the secondary flexible hinge (8) through a secondary flexible hinge (8). The rod end side of the lever (1) is connected; one end of the secondary lever (1) extends in the horizontal direction, and forms a free end through the extension section (14), at the free end of the secondary lever (1) Probes (9) are set so that the probes (9) are in contact with the force sensors (11) arranged on the micro-motion platform (10);

In the middle part of the transition rod (7), the transition rod counterweight (7b) is set by the fixed cantilever (7a), so that the center of gravity of the transition rod (7) is adjusted to the position of the secondary flexible hinge (8); The rod outer end of the first-level lever (3) is provided with a first-level lever counterweight (12), so that the center of gravity of the first-level lever (3) is adjusted to the position of the first-level fulcrum (5); The non-free end of the primary lever (1) is provided with a secondary lever counterweight (13), so that the secondary lever (1) and its extension (14), transition lever (7), cantilever (7a) and transition lever counterweight The common center of gravity of the block (7b) is adjusted to the position of the secondary fulcrum (2);

The loading method of the differential vertical micro-force loading device is to realize differential loading in one of the following ways:

Method 1: Load the loading weights of the same mass at the two input ends, and the probe is at the initial position at this time; set the force sensor to keep at the initial position, change the mass difference of the loading weights at the two input ends, and when the force Obtain different loading forces on the sensor;

Method 2: Load the loading weights of the same mass at the two input ends. At this time, the probe is at the initial position, and then change the mass difference between the loading weights at the two input ends to make the probe offset, and the probe will be moved by the force sensor. Gradually move from the offset position to the initial position, the closer the force sensor is to the initial position, the greater the force of the probe on the force sensor, and finally the loading force is determined by the mass difference between the weights loaded at the two input ends and the displacement of the force sensor the size of.

2. The loading method of the differential vertical micro-force loading device according to claim 1, characterized in that: in the differential vertical micro-force loading device, at the positions of the primary fulcrum and the secondary fulcrum, a The primary lever and the secondary lever are respectively suspended on the base through flexible hinges of each fulcrum, and the flexible hinges of each fulcrum are consistent with the direction of gravity.